Air check door closer



$ 2 Sheets-Sheet l H. A. SIMPSON AIR CHECK DOOR CLOSER INVENTORHerberifl Sim 95 1,

ATTORNEY Aug. 9 1949.

Filed July 5, 1947 Aug. 9, 1949. H. A. SIMPSON AIR CHECK DOOR CLOSER 2Sheets-Sheet 2 Filed July 5, 1947 m Tfi mm. m M Jr 6 Z E H Patented Aug.9 1 949 UNITED STATES PATENT OFFICE This invention relates to air checkdoor closers,

and more particularly to a door closer of the type having a coil springfor urging a door to closed position, and connected to the door bytelescoping means designed to utilize a cushion of air to preventslamming of the door.

One object of this invention is to provide a door closer of the abovenature having means to approximately equalize theeffect of the springforce regardless of the degree of extension of the spring.

Another object is to provide a device of the above nature which includesa stop to limit opening movement of the door.

Another object is to provide a device of the above nature which willhave the dependability and other characteristics of the more expensivehydraulic door checking devices, without the disadvantages attendantupon the use of a liquid.

A further object is to provide a device of the above nature in which theair cushion serves to actuate a brake which provides the greater part ofthe checking force, the air cushion being compressed only enough toactuate the brake.

Still another object is to provide a device of the above nature having abracket which is readily adaptable to mount the door closer at eitherthe inner or the outer side of the door, and also adaptable for use withdoors having either a right-hand or a left-hand swing.

A further object is to provide a door cioser of the above nature whichwill be simple inconstruction, inexpensive to manufacture, easy toinstall and manipulate, compact, ornamental in appearance, and veryefiicient and durable in use.

With these and other objects in view, there have been illustrated on theaccompanying drawing, two forms in which the invention may convenientlybe embodied in practice.

In the drawing,

Fig. 1 is a plan view of a door closer showing how it is attached to adoor and a door jamb.

Fig. 2 is a Side elevation of the same.

Fig. 3 is a cross-sectional view on the line 3-3 of Fig. 2, showing thespring housing.

Fig. 4 is a cross-sectional view, on a larger scale, taken along theline 4--4'- of Fig. 5; and showing details of the spring mechanism.

Fig. 5 is a cross-sectional view on the line 5-4: of Fig. 4, with theparts in the position they assume when the door is closed.

Fig.6 is a cross-sectional view similar to Fig. 5, showing the parts inthe position they assume when the door is open. 1

Fig. 7 is a fragmentary longitudinal sectional View on alarger scale ofthe brake cylinder and one form of brake mechanism.

Fig. 8 is a fragmentary longitudinal sectional view of the brakecylindenand a second form of brake mechanism employing apair of pivotedbrakeshoes. a r

Fig. 9 is a cross-sectional View taken on the line 2-9 of Fig. 8.

Fig. 10 is a longitudinal sectional view similar to Fig. 8, but rotated96 degrees therefrom,with

the brake shoes in inactive positions. I

Fig. 11 is a longitudinal sectional view of the same, simiiar to Fig.19, showing the brake shoes in braking" positions.

Fig. 12 is a longitudinal sectional viewof the brake cylinder, showing athird form of'com-pres 'sion cup mounting, with the compression cupinits inactive condition.

Fig. 13 is alongitudinal sectional view similar to Fig. 12, showing thecom ression cup in the shape it assumesunder pressure.-

' Referring now to the drawingsin which iike reference characters denotecorresponding parts throughoutthe several views, the letters C, D, and Jindicate a door closer,- a swingable door,- and a door ja mb,respectively.

The door closer Cis provided with a Z-shaped mounting bracket I8including parallel offset portions 1 1'; l2 for supporting" asubstantiaiiy cubical spring housing M ser-ewe M- and to being providedfor securing the bracket Hi to the jamb' J and the housing I3,respectively.- The housing H has an end wail is, a front wall iii, aback wail [8, a top wall i9, and a bottom wail 2E. The end wall f-Gisprovided with an outside reinforcing plate 24 tapped for receiving themounting screw l5, and the back wall is is provided with an 3 to receivea vertical pivot pin 21, mounted in the rear corners of the top andbottom walls I9, 26.

In order to limit the swinging movement of the bracket 24, the back walll8 terminates at a distance from the pivot pin 21, forming a stopabutment 28.

The bracket 24 is operatively connected with the door D by a telescopingguide housing, generally indicated by 29, having one end rigidly mountedupon one face of the bracket 24, its other end being connected to thedoor D by a. bracket 30 and screws 3|. The telescoping housing 29 willbe described in more detail hereinafter.

The spring housing l3 contains a coil spring 32 having an upperinwardly-bent end 33 received in a recess 34 of a spring base block 35.The block 35 is mounted upon a square shaft 36, held in centralapertures 31, 38 in the top and bottom housing walls i9, 20,respectively. The shaft 36 carries a toothed ratchet disk 39 exteriorlyof the housing for adjustable securement by a pivoted pawl 49, wherebyone end of the spring 32 may be selectively fixed against rotation, inseveral positions.

The spring 32 also has a lower outstanding end 4| confined in anaperture 42 in a vertical connecting plate 43 of a U-shaped yoke 44located within the spring housing I 3. The yoke 44 has upper and lowerhorizontal apertured plates 45, 46 which embrace the spring 32 and thespring base block 35, and receive the square shaft 36 rotatably in theapertures thereof. It will thus be seen that the U-shaped yoke 44 may berotated against the force of the spring 32.

In order to connect the swingable bracket 2-4 operatively to theU-shaped yoke 44, provision is made of a bent link 41 (Fig. pivotallysecured at one end to an anchor pin 48 held in apertures in the bracketflanges 25, 26, and secured at the other end in an aperture 48a in thevertical plate 43 of the U-shaped yoke 44.

The telescoping housing 29 includes an inner sliding guide tube 49threaded upon a mounting disk 50 fixed upon the outer face of theswingable bracket 24. An outer cylinder 5| of the housing 29 telescopesover the inner tube 49 at one end, and is provided with a domed cap 52at its other end, said cap being pivotally joined to the connectingbracket 39, as by a pin 53,

The action of the spring 32 in closing the door is checked by mechanismwhich includes a piston rod 54 threaded into the mounting disk 59 by areduced end 55, and extending concentrically within the inner guide tube49, and the outer cylinder 5!.

Brake mechanism Referring now to Fig. 7, the piston rod 54 is providedwith an extension 56 which includes an integral sleeve portion 51slidably embracing the end of the rod 54. The rod extension 56 isretained for limited sliding movement upon the rod 54 by a pair ofdiametrically opposed slots 58 in the sleeve portion 51, which receive across pin 59 fixed in the rod 54.

The ends of the cross pin 59 support a tubular portion 60 of a rigidbacking washer 6| in fixed position relative to the rod 54 andexteriorly of the extension 56. The washer Bl serves as an abutment fora flexible brake cup 62 of a diameter to fit within the cylinder 5|. Anut 63 threaded upon the outer end of the extension 56 holds thereon aretaining rigid washer 64, a flexible compression cup 65 preferably ofleather and a rigid expander cone 66 having a frustoconical peripheralsurface 61. A restoring coil spring 68 is disposed upon the extension 56and normally holds the expander cone 66 and the brake cup 62 insubstantially disengaged relation. A headed screw 69 is loosely threadedin the end cap 52 to serve as an adjustable bleed valve,

whereby the speed of operation of the door closer will be governed.

Operation In the operation of the door closer, opening movement of thedoor D, by means of the telescoping means 29, will swing the bracket 24from the position shown in Fig. 5 to the position shown in Fig. 6,against the force of the spring 32. The toothed disk 39 and the pawl 40will first have been adjusted to tension the spring 32 to produce adesired closing force. As the yoke 44 is swung, the spring 32 willundergo a build-up," or increase in tension. It will be noted, however,that the effective radius at which the link 4'! applies its force to theyoke 44 will increase as the yoke is swung, whereby the spring build-upwill be approximately compensated for and substantially the same closingforce will be exerted upon the door at all positions thereof.

The force of the spring 32 will be transferred to the door through thelever action of the tube 49 and the cylinder 5| telescoping thereon,thereby relieving the piston rod 54 and check mechanism of any sidethrust.

When the door starts to close, the piston rod 54 will move inwardly inthe cylinder 5i (to the right in Fig. 7), and as soon as air pressure ispicked up by the flexible compression cup 85, the rod extension 56, withthe expander cone 66 thereon, will be retarded against the force of thespring 68, thereby pressing the frusto-conical surface 6'! of said coneinto the brake cup 62. The cup 62, being flexible, will be expanded bythe cone not only at its edge, but also at the root of its cylindricalportion, due to a tendency of said cup to flatten under pressure.Accordingly, the air pressure against the compression cup 65 will causethe cup 62 to act as a frictional brake against the cylinder wall, andonly a minor and incidental part of the direct checking force will beprovided by said air pressure.

The bleed valve 89 will serve, as in the more conventional air checkdoor closures, to control the speed at which the air is released, andhence the speed of the closing movement.

Second form In the second form of the invention, shown in Figs. 8, 9,10, and 11, provision is made of an outer cylinder 10 and a piston rod Hmounted in all respects as the cylinder 5| and piston rod 54 of thefirst form. The piston rod H is provided with an extension 72 comprisinga sleeve portion 13 slidable on therod 7|, and a threaded stud l4 fixedin one end of the sleeve portion 13.

The extension 12 is secured for limited sliding movement on the rod 54 ba pair of slots 15 in the sides of the sleeve portion 13 which receiveprojecting end portions of a cross pin 16 fixed in the piston rod H. Theends of the cross pin 16 are provided with heads 11 which retain thelegs of a pair of U-shaped cam members 18 upon the cross pin 16 at eachexterior side of the sleeve portion 13-said cross pin being received inslots 18a extending inwardly from the ends of the legs of said U-shapedcam members 18. The slots 1811 are so proportioned that when the partsare in inactive position, as in Fig. 10, the cross pin 76 will engagethe inner ends of said slots 18a.

The outer curved parts of the .U-shaped cam members 18 are engaged atone edge bya pair .of fulcrum hooks 19, each forme'dcentrally on theinside of one of a pair of semi cylindrical brake shoes 80. The brakeshoes are further provided with frictional facings 8| upon their outersurfaces, and have inwardly turnedears 81a at their forward edges. g v IThe stud 14 of the rod extension 12 is provided with a nut 82 threadedthereon for coaction with a shoulder 83 of the rod extension 12 to holda flexible compression cup 83a having a retaining washer 84 and abackingwasher 85,.

As a means for holding the rod extension I2 .and compression cup 8 3anormally in theirmo'st extended position, a restoring coil spring 85 isprovided upon the extension 12, The spring 86 bears at one end againstthe rigid backing washer 85, and at the other end against the .U-shapedcam members 13 through the medium of a hearing ring 81.

The modified form of the device shown in Figs. 8, 9, 10 and 11 willoperate generally in the same manner as described above, except that thecamactuated brake shoes perform the braking function. In this device,when the compression cup 8341 picks up air pressure, said cup 83a,acting through the ears 81a, will press the brake shoes 88 rearwardlywith relation to the cross pin 16 whereby the U-shaped cam members 18will be tilted as shown in Fig. 11. Inasmuch as the cross pin 18 engagesthe inner ends of the slots 18a, the cam members 18 will have aneffectively greater radius when tilted and will press the brake shoes 88outwardly into frictional braking engagement with the cylinder surface.

Third form The third form of the invention shown in Figs. 12 and 13includes generally the same structure as was disclosed in the firstform, shown in Figs. 1 to 7, but is distinguished therefrom by animproved specific mounting for the compression cup.

In this form, a flexible compression cup 88 is mounted upon the end of arod extension 89 for sliding movement within an outer cylinder 90. Abacking for the cup 88 is provided by a rigid expander cone 9| having arearwardly-extending frusto-conical surface 92 and a front surfaceincludin a frusto-conical portion 93 surrounding a flat aperturedtransverse central portion 94, received upon the rod extension 89. A nut95 and a washer 98 serve to hold the cup 88 in its assembled relationagainst the flat central portion 94 of the cone 9 I.

It will be understood that the rod extension 89, and the expander cone9| are the counterparts of the extension 56 and the cone 66 as shown inFig. '7. A restoring spring 91 performs the same function as therestoring spring 68 in the first form.

In the operation of the third form of the invention shown in Figs. 12and 13, a frusto-conical front portion 93 of the expander cone 9|permits the compression cup 88 to flex rearwardly under the influence ofpressure in the cylinder 90, thereby assuming the shape shown in Fig.13.

The purpose of this feature is to provide repeated flexing of the cup 88with each movement of the door closer, thereby preventing the cupmaterial from taking a set and thus failing to pick up compression. Thisconstruction also pre-- vents excessive friction or vacuum drag, such as6 sometimesoccurredin prior door closures'dm?" ing the return stroke ofthe piston. I

Further, the mounting bracket in is'equally well adapted to provideeitherright or left-hand mountings merely by rotating the-,doorcloser.1- degrees with relation to said bracket, said tion beingpermittedby the releasable clamping screw is secured in the reinforcingplate 2! .or 22, as the case maybe. Thus, the'bracket [0, when insertedfrom the position shown in 2,

will be adapted for mounting the door closer in reversed position uponthe opposite door jambm While the improved door closer has been .hereindescribed as applied in an inside mounting-it may, if desired, also beapplied to a door closer in an outside mounting. In this .case. the-1Z-shaped mounting bracket will be appliedto the upper rail of the. door,and the offset bracket portion I2 will be secured by the screw I 51110the back reinforcing plate 22, the connecting bracket 38 being securedto the door lintel.

One advantage of the three forms of door closers herein disclosed isthat only a small degree of air pressure is required to operate thecheck means. The air compression cup is never called upon to resistexcessive pressure, and consequently will have a long life and will notrequire constant adjustment.

Further, the closer not Only has the dependability and smoothness ofoperation found in hydraulic door closers, but will also maintainuniform operation despite changes of temperature.

The form of the invention shown in Figs. 8, 9, 10, and 11 has been foundparticularly suitable for heavy doors because of its large brakingsurface.

The brake mechanisms herein disclosed are claimed in my copendingdivisional application Serial Number 64,851, filed December 11, 1948,

u entitled Check mechanism for door closers.

While there have been disclosed in this specification three forms inwhich the invention may be embodied, it is to be understood that theseforms are shown for the purpose of illustration only, and that theinvention is not to be limited to the specific disclosures, but may bemodified and embodied in various other forms Without departing from itsspirit. In short, the invention includes all the modifications andembodiments coming within the scope of the following claims.

Having thus fully described the invention, what is claimed as new, andfor which it is desired to secure Letters Patent, is:

1. In a door closer, a coil spring, means securing one end of saidspring in fixed position, a rotatable yoke embracing said spring andsecurin the other end thereof, swingable means adapted for connection toa door and mounted upon a fixed pivot adjacent said yoke, and a linkconnected at one end to said swingable means and at its other end to anouter edge of said yoke, whereby the spring is adapted to exert a forcethrough said yoke, link, and swingable means to close the door.

2. In a door closer, a mounting means including a housing open on oneside, a shaft adjustably secured in opposite walls of said housing, acoil spring secured at one end thereof to said shaft, a yoke rotatablymounted on the shaft within said housing and embracing said spring, saidspring being secured at its other end to said yoke, swingable meansadapted for connection to a door and including a bracket portion adaptedto close the open side of the housing and pivoted therein, and a linkconnected at one end to said bracket portion and at its other end to anedge of said yoke.

3. The invention defined in claim 2, wherein the bracket portion in itsclosed position lies contiguous to the yoke, and the link extends pastsaid shaft, whereby the efiective radius of the force applied to theyoke by the link will increase as the bracket portion i moved to openposition.

' 4. In a door closer, at swingable means adapted for connection to adoor to urge the door to closed 10 position, and means for mounting saidswingable means including a housing, a spring therein connected to saidswingable means, a tapped reinforcing plate secured to one side of saidhousing, a second tapped reinforcing plate secured to the rear of saidhousing, a bracket, and a screw whereby said plates may be selectivelyattached to said bracket in erect and inverted position, for inside,outside, left-hand and right-hand mounting of the door closer.

HERBERT A. SIMPSON.

,8 REFERENCES CITED The following references are of record in the fileof this patent:

UNITED STATES PATENTS Number Name Date 669,118 Kindermann Mar. 5, 1901703,371 Beauregard July 1, 1902 859,521 Robertson July 9, 1907 931,701Newsam Aug. 17, 1909 1,266,864 Schmidt May 21, 1918 1,425,271 MukdenAug. 8, 1922 1,491,388 Foster Apr. 22, 1924 1,528,195 Bush Mar. 3, 19251,662,395 Norton Mar. 13, 1928 1,832,699 Garrison Nov. 17, 19312,066,795 Moore Jan. 5, 1937 2,220,234 Hadaway Nov. 5, 1940 2,416,828Hamre Mar. 4, 1947

